About Take Two®

Airs Weekdays 2 to 3 p.m.

Join Take Two each weekday at 9 AM where we’ll translate the day’s headlines for Southern California, making sense of the news and cultural events that people are talking about. Find us on 89.3 KPCC, hosted by A Martinez.

A view of the Los Angeles city skyline as heavy smog shrouds the city in California on May 31, 2015. AFP PHOTO/ MARK RALSTON (Photo credit should read MARK RALSTON/AFP/Getty Images)
MARK RALSTON/AFP/Getty Images

Air quality experts have long maintained that living close to a highway can be bad for your health. In Southern California where space is limited, however, hundreds of thousands of people live within a quarter mile of a freeway. But a change in city building code enforcement might provide some relief.

Mayor Eric Garcetti's office announced yesterday that building inspectors must now check for air filtration systems in new homes built near freeways — but that's just new homes.

Even with filtration systems, Sean Hecht, a professor of environmental law at UCLA's Emmett Institute on Climate Change and the Environment, says people living near freeways are still at risk.

He shared his thoughts with Take Two.

What should people living near freeways be most concerned about?

Living near a freeway means you're exposed to ultrafine particulate matter that comes from diesel exhaust that comes from other combustion from vehicles on the freeway. There's also oxides of nitrogen, which create ground-level ozone.

Particulate matter is especially dangerous for folks who live or work or play within a short distance of a freeway.

What kind of health effects are we talking about here?

There's been a lot of research on asthma and other respiratory diseases and heart disease. With children, asthma is a particularly terrible problem for people who live near freeways, and it's very well documented about what the impact of particulate matter is.

Ultrafine particles can penetrate the cell walls in people's lungs and create more long-term heart and lung related problems. And there's additional cancer risk because of those same types of pollutants.

Say I live right next to a freeway and I put an air filter right by a window...

The high-efficiency filters can make a difference with particulate matter. You always have to have your windows and doors closed for it to work properly. It can have an impact. As I mentioned, that's not what public health officials recommend. They don't believe it's adequate. It only protects against the particulate matter and not against the other pollutants, so you're still getting contaminants.

If you live near a freeway, you're going to be outside sometimes. You're gonna be walking to or from your car. You might be exercising. It doesn't protect people — but it helps. It's better than not having those filters.

So, it sounds like no one big solution can take care of everything.

No, and unfortunately, we have a housing crisis in California, and it's motivated a lot of units to be built without regard to how close they are to a freeway. It's a very tough problem. The best answer from a health standpoint is not to build near the freeways.